Disposable diaper having an adhesive closure system and method of construction therefor

Abstract

A disposable diaper having a moisture-impermeable backing sheet and a moisture-retaining layer superposed on the backing sheet and including a facing sheet substantially coextensive with the backing sheet is provided with an adhesive closure system which comprises a composite made up of a plurality of superposed adhesive layers having different physical properties. An anchoring adhesive layer is adhesively attached to the backing sheet and to the facing sheet, and a securing adhesive layer is provided on the facing sheet, preferably adhesively attached to the anchoring layer through the facing sheet, and presents a tacky surface facing in the same direction as the exterior surface of the diaper facing sheet. Transfer tape is used to deposit individual layers of adhesive so as to form the composite.

I claim: 
     
       1. A disposable diaper having an inside surface for direction toward an infant when the diaper is worn by that infant and an outside surface for direction away from said infant and including a flexible backing sheet of substantially moisture-impermeable material forming the diaper outside surface, a moisture-retaining layer having a pad of absorbent material superposed on said backing sheet and attached thereto and a porous facing sheet substantially coextensive with said backing sheet and forming the diaper inside surface, and a pressure sensitive adhesive closure within the peripheral limits of the diaper and comprising a layer of anchoring adhesive between said backing sheet and said facing sheet at a marginal location on said diaper and adhesively attached both to said backing sheet and to said facing sheet and a layer of pressure sensitive securing adhesive on said facing sheet, substantially coextensive with said layer of anchoring adhesive and adhesively attached to said anchoring adhesive through said facing sheet and presenting a tacky surface in the same direction as the diaper inside surface; said anchoring adhesive layer having greater adhesion to the backing sheet than said securing adhesive layer, and said securing adhesive layer having a greater quick stick property relative to the backing sheet than said anchoring adhesive layer. 
     
     
       2. The disposable diaper in accordance with claim 1 wherein said securing adhesive layer comprises a styrene-isoprene block copolymer tackified with a polyolefin. 
     
     
       3. The disposable diaper in accordance with claim 1 wherein said anchoring adhesive layer comprises a styrene-butadiene copolymer tackified with a pinene resin.